DIRECTIONS FOR RISK TREE EVALUATION FORM
The following are the instructions for filling out and completing the Risk Tree Evaluation form.
Each step corresponds to a section on the evaluation sheet. It is important that all steps be followed
in the exact order that they are presented here. By Following each step you will reach a final numeric
hazard rating. This number can then be used to determine your course of action. Failure to not
follow these directions in the order they are presented here will result in inaccurate results due to
improper calculations.
Location: The overall area that the tree, or trees, to be inspected
are located. This could be a city, town, campground,
roadway, etc.
Date: The month, day and year of when the inspection
occurred.
Inspector(s): The qualified individual, or individuals, that
performed the inspection and assessed the tree’s
condition.
Tree #: The unique identification number assigned to the tree.
This can be a number that already exists from a
previous inventory or it can be a newly created
number specific to this evaluation.
Sp. Species code. A unique code representing the tree’s
species. This code may be made up of numbers or
letters. (i.e.: AR= Acer rubrum)
DBH Diameter at breast height. The tree’s diameter
measured at 4.5 feet from the ground.
Location information The precise location of the tree being evaluated. It
can refer to GIS/GPS coordinates, street address or
the location on a map.
Defect Code(s) A designated code can be entered into the form to
show what defect is present on the tree. The codes
provide each user with a uniform method for entering
defects.
Probability of Failure The number represents different degrees of severity,
pertaining to the amount and type of damage that
exists on the surveyed tree. There are four classes in
this category; they are low, moderate, high, and
extremely high
Size of Defective Part(s) The size, in diameter, of the largest part that is
defective. There are three size classes; less than 4
inches, 4 to 20 inches, greater than 20 inches.
Probability of Target Impact The number which represents the likelihood that the
tree would impact life or property should it fail. The
three ratings are based on the target areas level and
frequency of use. The level of use ranges from
occasional to intermittent to frequent.
Other Risk Factors An optional category that is available for
professionals to use if they feel that the hazard rating
should be further adjusted. For example, some risk
assessment surveyors will use species as a guide to
establish a rating in this category
Description of Risk Factors Here you will be able to ad notes to add further
description of the “other risk factors”
Hazard Risk Rating The rating is the sum of columns one through four.
This number value helps determine the course of
action to be taken to remedy the problem
Corrective Action Code(s) A particular code that is entered into the form. This
code corresponds to an action that is needed to correct
the problem. This could include removing the
defective part by pruning, removing the entire tree,
relocating the target, or securing the area.
Action Completed The date of when the problem was corrected as well
as the initials of the person responsible for insuring
that was correction was made.